The deep waters of California are creating what is known as an oases of biodiversity. This finding is important for marine wildlife in a world where human population growth and overfishing have caused marine wildlife to struggle.
Off the coast of the state are submarine mountains that are thousands of feet high and provide the ideal ecosystem for wildlife to grow and prosper.
Known as seamounts, these mountains can be distinguished in a few ways to fit the classification:
- 1,000 meters or higher in height
- Steep sides
- Elliptical or circular in shape
California’s seamounts are massive, and the largest of the sea mountains is called Davidson Seamount.
Davidson Seamount is 4,101 feet below the sea level, yet the massive underwater mountain is 7,480 feet tall.
How Seamounts Are Formed
Davidson, and all other seamounts, are typically formed due to volcanic eruptions. These eruptions often occur under the water, but in many cases of the larger seamounts, the eruptions spewed ash out of the ocean waters to breach the surface.
Hawaii’s islands were formed due to this same natural event.
California’s Seamounts Are Millions of Years Old
The seamounts found off of the coast of California have been extensively researched, and researchers believe that the seamounts were formed during volcanic eruptions some 7 – 16 million years ago.
The “youngest” seamount off of the coast of California is estimated to be 2.8 million years old.
Researchers estimate that there are over 30,000 seamounts all over the world. California is home to 56 seamounts that have been identified. This chain of underwater mountains spans 200 nautical miles off of the shore and is known as the exclusive economic zone (EEZ).
Seamounts Provide an Ecological Oases
Seamounts play a large role in the biodiversity of the world’s oceans. Most of the seamounts in the world are highly productive. These spots are biodiverse, and this is primarily due to the change in currents caused by underwater mountains.
Reduced sediment loss occurs as a result of the mountains, which allows for a greater abundance of food and nutrient-rich water.
California’s seamounts haven’t been explored thoroughly to be able to determine the exact extent of biodiversity in the area. Davidson Seamount has been studied enough to know that the mountain is home to 25 species of cold-water coral. Surveys of the area also find that the seamounts are highly diverse, but further research needs to be conducted in the area.
A recent survey of 3 seamounts found 13 new invertebrates discovered as well as a sponge species, urchin and coral.
Increased prey due to the highly diverse environment has attracted seabirds and cetaceans that are preying on sea life near the seamounts. The seamounts have also been studied for their link to shark navigation. Studies show that sharks will use the magnetic signatures, unique to each seamount, to navigate.
The finding gives credence to the idea that large, top predators in the ocean waters rely on seamounts for feeding, resting and mating.
Sadly, just 1.5% of the world’s seamounts are in protected areas, which allows for devastation of these areas due to human activity, primarily fishing and mining.